Monosodium citrate, more correctly, sodium dihydrogen citrate, is an acid salt of citric acid. Disodium citrate and trisodium citrate are also known. It can be prepared by partial neutralisation of an aqueous solution of sodium bicarbonate or carbonate with citric acid. It is highly soluble in water and practically insoluble in ethanol. Monosodium citrate is used as an anticoagulant in donated blood.